Diamond dressing tool

ABSTRACT

A diamond dressing tool comprising a body having a shank, an insert holder mounted on said body and a diamond insert press fitted into said insert holder. The insert holder and body have radially extending surfaces which are engaged with one another and a drive screw holds the body and insert holder in assembled relation.

United States Patent [191 Kohlstrunk 1 Jan. 9 1973 [54] DIAMOND DRESSING TOOL [75] Inventor: Arthur T. Kohlstrunk,

Mich.

[73] Assignee: Abrasive Diamond Tool Company,

Madison Heights, Mich.

[22] Filed: Dec. 18, 1970 [21] Appl. No.: 99,419

Livonia,

[S2] U.S. Cl. ..l25/11 N [51] Int. Cl. ..B24b 53/12 [58] Field of Search ..l25/ll N, 39

[56] References Cited UNITED STATES PATENTS 4,452,735 7/1969 Bullock ....125 39 2,302,921 11/1942 Spencer ..l25/39 Primary Examiner-Harold D. Whitehead Attorney-Barnes, Kisselle, Raisch & Choate 57 ABSTRACT A diamond dressing tool comprising a body having a shank, an insert holder mounted on said body and a diamond insert press fitted into said insert holder. The insert holder and body have radially extending surfaces which are engaged with one another and a drive screw holds the body and insert holder in assembled relation.

4 Claims, 8 Drawing Figures 'PATENTEDJAN 9 Ian 3.709.207

mvszvron ARTHUR T. KOHLSTRUNK mun/ I {v ATTORNEYS DIAMOND DRESSING TOOL This invention relates to diamond dressing tools and particularly to diamond dressing tools of the type where the diamond can be indexed without removing the tool from its mounting fixture.

BACKGROUND OF THE INVENTION In the dressing of grinding wheels and the like, it is common to utilize a diamond dressing tool. In order to provide a sharp dressing point, it has heretofore been suggested that the tool be indexable while it is mounted on the mounting fixture. Such indexable diamond dressing tools commonly utilize crimping or swaging operations to assemble the diamond holder to the portion of the tool that is mounted in the mounting fixture. A problem arises with crimping in that there may be a loss of rigidity and resistance to turning moments should the crimping force be reduced due to improper assembly or heavy use in the field. Any such loss of rigidity or resistance will cause the diamond to flutter while dressing a grinding wheel resulting in a poor dressing action or fractured diamond. Severe usage could cause the entire assembly to come apart since a very small amount of crimped metal around the diamond insert holds the component part together. A major difficulty with the swaging method is the tendency for the metal to fracture and tear in a critical area when cold formed. Once the metal has been fractured or torn during assembly of the component parts, rigidity and resistance to turning moments will be seriously reduced again resulting in poor dressing performance during the dressing operation.

Among the objects of the invention are to provide a simple dressing tool which will positively hold the component parts in assembled relation without altering, fracturing or weakening the base metal in the components; which will hold the components in proper relation; which utilizes a minimum number of parts.

SUMMARY OF THE INVENTION A diamond dressing tool comprising a body having a shank, an insert holder mounted on said body and a diamond insert press fitted into said insert holder. The insert holder and body have radially extending surfaces which are engaged with one another and a drive screw holds the body and insert holder in assembled relation.

DESCRIPTION OF THE DRAWINGS stages of manufacture.

DESCRIPTION Referring to FIGS. 1 and 7, the diamond dressing tool embodying the invention comprises a body 10, a diamond insert holder 11 and a diamond insert 12 which are assembled together by use of a metal lock The tool body 10 includes a shank 18 and aradially extending flange or web 19 that defines a radial surface 20. The body 10 further includes a cylindrical axial extension 21. I

The diamond insert holder 11 cludes a cylindrical opening 22 and a radially extending wall 23 that has a cylindrical opening 24 which is of substantially the same diameter as the diameter of the axial extension 21. The diamond insert 12 includes a cylindrical opening 12a which extends entirely therethrough and is surrounded by a countersunk recess 12b at one end thereof. A mass or body 25 of sintered tungsten metal powder supports the diamond 26 in one end of the diamond insert holder 12.

As shown in FIGS. 4 and 5, the body 12 is formed from a blank 27 that has the cylindrical recess 23 therein by positioning the mass 25 of unsintered tungsten carbide in the opening and the diamond 26 in position and then sintering the blank. The blank is then cut along the line 28 to the shape shown in FIG. 6.

In order to assemble the tool, the diamond insert holder 11 is first placed with the radial surface 30 of wall 23 against the surface 20 in the axial extension 21 extending through the opening 24 and the drive screw 15 is driven into the axial opening 31 in the body 10 against the lock washer 13. This mounts the insert holder 11 on the body 10 in the desired frictional relationship so that it is firmly held and yet may be indexed by engaging a tool with the hexagonal exterior 32. The end of the axial extension 21 engages the head 17 of screw 15 to produce a predetermined force with which the insert holder 11 is frictionally held on the body 10.

The diamond insert 12 is then press fitted into the opening 22 to produce the tool shown in FIG. 8. The tool can then be dressed along the line33 as desired to provide the desired exposure of the diamond 26 and produce the final shape shown in FIG. 1.

By utilizing a simple commercially available drive screw 15, the component parts of the tool are positively assembled without altering, fracturing or weakening the base metal in either the body 10 or the insert holder 11. The helical gripping surfaces 16 of the drive screw 15 do not physically change or disturb the critical mounting extension 21 on the body 10 in the area where the insert holder 11 is assembled on the body 10. Once the drive screw 15 is seated, compressing lock washer 13, the insert holder 11 is held in full engagement against the body 10 at the surface 20 and around the periphery of the extension 21. No outside force will dislodge or loosen the screw 15 resulting in a constant torque throughout the useful life of the diamond.

lclaim: l. A diamond dressing tool comprising a body including a shank portion, said body having a radially extending surface adjacent one end thereof and an axially extending opening in said one end thereof, an insert holder having an axially extending opening therein and a radial portion at one end engaging the radial surface of said body, a lock washer engaging the opposite surface of said I radial portion,

is cylindrical and ina drive screw extending through said opening in said insert holder and threaded into said opening in said body,

said drive screw having a head engaging said lock washer and urging said lock washer against said the base of said recess and the outer surface of said head being spaced from one another,

said body including an axial extension extending axially outwardly through said opening in said radial wall of said insert holder,

said head of said drive screw abuttingsaid axial extension.

2. The combination set forth in claim 1 wherein said.

axial extension is cylindrical.

3. The combination set forth in claim 1 wherein said opening in said insert holder is cylindrical.

4. The combination set forth in claim 1 wherein said screw has a generally cylindrical body with helical surfaces and said opening in said body into which said screw extends is generally cylindrical. 

1. A diamond dressing tool comprising a body including a shank portion, said body having a radially extending surface adjacent one end thereof and an axially extending opening in said one end thereof, an insert holder having an axially extending opening therein and a radial portion at one end engaging the radial surface of said body, a lock washer engaging the opposite surface of said radial portion, a drive screw extending through said opening in said insert holder and threaded into said opening in said body, said drive screw having a head engaging said lock washer and urging said lock washer against said radial portion of said insert holder and in turn said radial portion of said insert holder against said radial surface of said body, and a diamond insert comprising a diamond and a metal body in which said diamond is embedded, said diamond insert being press fitted into the other end of said opening of said insert holder, said insert having an axially extending recess in the end thereof opposite said diamond into which said head of said drive screw extends and defining an annular wall engaging said lock washer and surrounding said head of said drive screw, the base of said recess and the outer surface of said head being spaced from one another, said body including an axial extension extending axially outwardly through said opening in said radIal wall of said insert holder, said head of said drive screw abutting said axial extension.
 2. The combination set forth in claim 1 wherein said axial extension is cylindrical.
 3. The combination set forth in claim 1 wherein said opening in said insert holder is cylindrical.
 4. The combination set forth in claim 1 wherein said screw has a generally cylindrical body with helical surfaces and said opening in said body into which said screw extends is generally cylindrical. 